Touch pressure detectable touch input device including display module

ABSTRACT

A touch input device detecting a touch position and a touch pressure may be provided. The touch input device includes a display module which includes a first layer made of glass or plastic and a second layer which is disposed under the first layer and is made of glass or plastic; a plurality of touch electrodes which are formed within the display module and are for detecting the touch position and the touch pressure; and a reference electrode which is disposed apart from the touch electrode.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. §119 to KoreanPatent Application No. 10-2015-0127566, filed Sep. 9, 2015, which isincorporated herein by reference.

BACKGROUND

Field

The present disclosure relates to a touch pressure detectable touchinput device including a display module, and more particularly to atouch pressure detectable touch input device including a display modulecapable of detecting a touch position and a touch pressure by using acapacitance change amount.

Description of the Related Art

Various kinds of input devices are being used to operate a computingsystem. For example, the input device includes a button, key, joystickand touch screen. Since the touch screen is easy and simple to operate,the touch screen is increasingly being used in operation of thecomputing system.

The touch screen may constitute a touch surface of a touch input deviceincluding a touch sensor panel which may be a transparent panelincluding a touch-sensitive surface. The touch sensor panel is attachedto the front side of a display screen, and then the touch-sensitivesurface may cover the visible side of the display screen. The touchscreen allows a user to operate the computing system by simply touchingthe touch screen by a finger, etc. Generally, the computing systemrecognizes the touch and a position of the touch on the touch screen andanalyzes the touch, and thus, performs the operations in accordance withthe analysis.

Here, there is a demand for a touch input device capable of detectingnot only the touch position according to the touch on the touch screenbut a pressure magnitude of the touch without degrading the performanceof a display module.

SUMMARY

One embodiment is a touch input device detecting a touch position and atouch pressure may be provided. The touch input device includes: adisplay module which includes a first layer made of glass or plastic anda second layer which is disposed under the first layer and is made ofglass or plastic; a plurality of touch electrodes which are formedwithin the display module and are for detecting the touch position andthe touch pressure; and a reference electrode which is disposed apartfrom the touch electrode. A drive signal is applied to the touchelectrode and the touch position is detected by a sensing signalreceived from the touch electrode. An electrical signal which is changedby a capacitance between the touch electrode and the reference electrodeis detected from the touch electrode. The capacitance is changed by achange of a distance between the touch electrode and the referenceelectrode. The distance between the touch electrode and the referenceelectrode is changed by a bend of the display module. The touch pressureis detected based on the capacitance.

The touch input device may further include: a substrate which isdisposed under the display module; and a spacer layer which is disposedbetween the touch electrode and the reference electrode. A spacer layerretaining member having a predetermined thickness may be formed alongthe circumference of the upper portion of the substrate in order toretain the spacer layer. When the display module is bent by applying apressure to the display module, the spacer layer retaining member maynot be transformed. The reference electrode may be the substrate.

A liquid crystal layer may be disposed between the first layer and thesecond layer.

An organic material layer may be disposed between the first layer andthe second layer.

The touch electrode may be formed on the top surface of the first layer.

The touch electrode may be formed on the bottom surface of the firstlayer or on the top surface of the second layer.

The touch electrode may be a common electrode included in the displaymodule.

Another embodiment is a touch input device detecting a touch positionand a touch pressure. The touch input device includes: a display modulewhich includes a first layer made of glass or plastic and a second layerwhich is disposed under the first layer and is made of glass or plastic;a first electrode for detecting the touch position and the touchpressure and a second electrode for detecting the touch position, whichare formed within the display module; and a reference electrode which isdisposed apart from the first electrode. A drive signal is applied toany one of the first electrode and the second electrode, and the touchposition is detected by a sensing signal received from the other of thefirst electrode and the second electrode. An electrical signal which ischanged by a capacitance between the first electrode and the referenceelectrode is detected from the first electrode. The capacitance ischanged by a change of a distance between the first electrode and thereference electrode. The distance between the first electrode and thereference electrode is changed by a bend of the display module. Touchpressure is detected based on the capacitance.

The touch input device may further include: a substrate which isdisposed under the display module; and a spacer layer which is disposedbetween the first electrode and the reference electrode. A spacer layerretaining member having a predetermined thickness may be formed alongthe circumference of the upper portion of the substrate in order toretain the spacer layer. When the display module is bent by applying apressure to the display module, the spacer layer retaining member maynot be transformed. The reference electrode may be the substrate.

A liquid crystal layer may be disposed between the first layer and thesecond layer.

An organic material layer may be disposed between the first layer andthe second layer.

The first electrode and the second electrode may be formed on the topsurface of the first layer.

The first electrode and the second electrode may be formed on the bottomsurface of the first layer or on the top surface of the second layer.

The first electrode or the second electrode is a common electrodeincluded in the display module.

The second electrode may be formed on the top surface of the firstlayer, and the first electrode may be formed on the bottom surface ofthe first layer or on the top surface of the second layer.

The first electrode may be a common electrode included in the displaymodule.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1a is a schematic view for describing a capacitance type touchsensor panel 100 and the operation thereof in accordance with anembodiment of the present invention;

FIGS. 1b and 1c show various arrangements of a plurality of driveelectrodes and a plurality of receiving electrodes in accordance withthe embodiment of the present invention;

FIG. 2 is a schematic view for describing a capacitance type touchsensor panel 100 and the operation thereof in accordance with anotherembodiment of the present invention;

FIGS. 3a to 3e are conceptual views showing a relative position of thetouch sensor panel with respect to a display module in a touch inputdevice according to the embodiment of the present invention;

FIGS. 4a and 4b are views for describing a method for detecting a touchpressure on the basis of a mutual capacitance change amount in the touchinput device according to the embodiment of the present invention;

FIG. 5 is a block diagram showing a configuration for detecting thetouch pressure on the basis of a self-capacitance change amount in thetouch input device according to the embodiment of the present invention;

FIGS. 6a and 6b are views for describing a method for detecting thetouch pressure on the basis of the self-capacitance change amount in thetouch input device according to the embodiment of the present invention;

FIG. 7 is a cross sectional vies showing the arrangement of each of theelectrodes in the touch input device according to the embodiment of thepresent invention;

FIG. 8a is a view schematically showing that each electrode has beenarranged according to the embodiment of FIG. 7;

FIG. 8b is a cross sectional view showing that the drive electrode andthe receiving electrode are formed in the same layer within the displaymodule in the touch input device according to the embodiment of thepresent invention;

FIG. 9 is a cross sectional view showing the arrangement of each of theelectrodes in the touch input device according to another embodiment ofthe present invention;

FIGS. 10a and 10b are views schematically showing that each electrodehas been arranged according to the embodiment of FIG. 9; and

FIG. 11 is a cross sectional view showing that a pressure electrode hasbeen formed within the display module including an OLED panel in thetouch input device according to the embodiment of the present invention.

DETAILED DESCRIPTION

Specific embodiments of the present invention will be described indetail with reference to the accompanying drawings. The specificembodiments shown in the accompanying drawings will be described inenough detail that those skilled in the art are able to embody thepresent invention. Other embodiments other than the specific embodimentsare mutually different, but do not have to be mutually exclusive.Additionally, it should be understood that the following detaileddescription is not intended to be limited.

The detailed descriptions of the specific embodiments shown in theaccompanying drawings are intended to be read in connection with theaccompanying drawings, which are to be considered part of the entirewritten description. Any reference to direction or orientation is merelyintended for convenience of description and is not intended in any wayto limit the scope of the present invention.

Specifically, relative terms such as “lower,” “upper,” “horizontal,”“vertical,” “above,” “below,” “up,” “down,” “top” and “bottom” as wellas derivative thereof (e.g., “horizontally,” “downwardly,” “upwardly,”etc.) should be construed to refer to the orientation as then describedor as shown in the drawing under discussion. These relative terms arefor convenience of description only and do not require that theapparatus be constructed or operated in a particular orientation.

Terms such as “attached,” “affixed,” “connected,” “coupled,”“interconnected,” and similar refer to a relationship wherein structuresare attached, connected or fixed to one another either directly orindirectly through intervening structures, as well as both movable orrigid attachments or relationships, unless expressly describedotherwise.

A touch input device according to the embodiment of the presentinvention can be used not only in a portable electronic product such asa smartphone, smartwatch, tablet PC, laptop computer, personal digitalassistant (PDA), MP3 player, camera, camcorder, electronic dictionary,etc., but also in an electric home appliance such as a home PC, TV, DVD,refrigerator, air conditioner, microwave, etc. Also, the touch pressuredetectable touch input device including a display module in accordancewith the embodiment of the present invention can be used withoutlimitation in all of the products requiring a device for display andinput such as an industrial control device, a medical device, etc.

A touch input device according to an embodiment of the present inventionwill be described with reference to the accompanying drawings. While acapacitance type touch sensor panel 100 and a pressure detection module400 are described below, the touch sensor panel 100 and the pressuredetection module 400 may be adopted, which are capable of detecting atouch position and/or touch pressure by any method.

FIG. 1a is a schematic view for describing the capacitance type touchsensor panel 100 and the operation thereof in accordance with anembodiment of the present invention. Referring to FIG. 1a , the touchsensor panel 100 according to the embodiment of the present inventionmay include a plurality of drive electrodes TX1 to TXn and a pluralityof receiving electrodes RX1 to RXm, and may include a drive unit 120which applies a drive signal to the plurality of drive electrodes TX1 toTXn for the purpose of the operation of the touch sensor panel 100, anda sensing unit 110 which detects the touch and the touch position byreceiving a sensing signal including information on a capacitance changeamount changing according to the touch on the touch surface of the touchsensor panel 100.

As shown in FIG. 1a , the touch sensor panel 100 may include theplurality of drive electrodes TX1 to TXn and the plurality of receivingelectrodes RX1 to RXm. FIG. 1a shows that the plurality of driveelectrodes TX1 to TXn and the plurality of receiving electrodes RX1 toRXm of the touch sensor panel 100 form an orthogonal array.

FIGS. 1b and 1c show various arrangements of the plurality of driveelectrodes and the plurality of receiving electrodes in accordance withthe embodiment of the present invention. FIG. 1b shows that a driveelectrode 10 and a receiving electrode 20 which have been disposed inseparate layers form an orthogonal array. That is, the receivingelectrode 20 may be extended in a direction crossing the direction inwhich the drive electrode 10 is extended. FIG. 1c shows that the driveelectrode 10 and the receiving electrode 20 have been disposed in thesame layer. In this case, the receiving electrode 20 may be extended inparallel with the direction in which the drive electrode 10 is extended.

However, the present invention is not limited to this. The plurality ofdrive electrodes 10 and the plurality of receiving electrodes 20 has anarray of arbitrary dimension, for example, a diagonal array, aconcentric array, a 3-dimensional random array, etc., and an arrayobtained by the application of them. Here, “n” and “m” are positiveintegers and may be the same as each other or may have different values.The magnitude of the value may be changed depending on the embodiment.

As shown in FIGS. 1a and 1b , the plurality of drive electrodes TX1 toTXn and the plurality of receiving electrodes RX1 to RXm may be arrangedto cross each other. The drive electrode TX may include the plurality ofdrive electrodes TX1 to TXn extending in a first axial direction. Thereceiving electrode RX may include the plurality of receiving electrodesRX1 to RXm extending in a second axial direction crossing the firstaxial direction.

In the touch sensor panel 100 according to the embodiment of the presentinvention, the plurality of drive electrodes TX1 to TXn and theplurality of receiving electrodes RX1 to RXm may be formed in the samelayer. For example, the plurality of drive electrodes TX1 to TXn and theplurality of receiving electrodes RX1 to RXm may be formed on the sameside of an insulation layer (not shown). Also, the plurality of driveelectrodes TX1 to TXn and the plurality of receiving electrodes RX1 toRXm may be formed in the different layers. For example, the plurality ofdrive electrodes TX1 to TXn and the plurality of receiving electrodesRX1 to RXm may be formed on both sides of one insulation layer (notshown) respectively, or the plurality of drive electrodes TX1 to TXn maybe formed on a side of a first insulation layer (not shown) and theplurality of receiving electrodes RX1 to RXm may be formed on a side ofa second insulation layer (not shown) different from the firstinsulation layer.

The plurality of drive electrodes TX1 to TXn and the plurality ofreceiving electrodes RX1 to RXm may be made of a transparent conductivematerial (for example, indium tin oxide (ITO) or antimony tin oxide(ATO) which is made of tin oxide (SnO₂), and indium oxide (In₂O₃),etc.), or the like. However, this is only an example. The driveelectrode TX and the receiving electrode RX may be also made of anothertransparent conductive material or an opaque conductive material. Forinstance, the drive electrode TX and the receiving electrode RX may beformed to include at least any one of silver ink, copper or carbonnanotube (CNT). Also, the drive electrode TX and the receiving electrodeRX may be made of metal mesh or nano silver.

The drive unit 120 according to the embodiment of the present inventionmay apply a drive signal to the drive electrodes TX1 to TXn. In theembodiment of the present invention, one drive signal may besequentially applied at a time to the first drive electrode TX1 to then-th drive electrode TXn. The drive signal may be applied againrepeatedly. This is only an example. The drive signal may be applied tothe plurality of drive electrodes at the same time in accordance withthe embodiment.

Through the receiving electrodes RX1 to RXm, the sensing unit 110receives the sensing signal including information on a capacitance (Cm)101 generated between the receiving electrodes RX1 to RXm and the driveelectrodes TX1 to TXn to which the drive signal has been applied,thereby detecting whether or not the touch has occurred and where thetouch has occurred. For example, the sensing signal may be a signalcoupled by the capacitance (CM) 101 generated between the receivingelectrode RX and the drive electrode TX to which the drive signal hasbeen applied. As such, the process of sensing the drive signal appliedfrom the first drive electrode TX1 to the n-th drive electrode TXnthrough the receiving electrodes RX1 to RXm can be referred to as aprocess of scanning the touch sensor panel 100.

For example, the sensing unit 110 may include a receiver (not shown)which is connected to each of the receiving electrodes RX1 to RXmthrough a switch. The switch becomes the on-state in a time intervalduring which the signal of the corresponding receiving electrode RX issensed, thereby allowing the receiver to sense the sensing signal fromthe receiving electrode RX. The receiver may include an amplifier (notshown) and a feedback capacitor coupled between the negative (−) inputterminal of the amplifier and the output terminal of the amplifier,i.e., coupled to a feedback path. Here, the positive (+) input terminalof the amplifier may be connected to the ground. Also, the receiver mayfurther include a reset switch which is connected in parallel with thefeedback capacitor. The reset switch may reset the conversion fromcurrent to voltage that is performed by the receiver. The negative inputterminal of the amplifier is connected to the corresponding receivingelectrode RX and receives and integrates a current signal includinginformation on the capacitance (CM) 101, and then converts theintegrated current signal into voltage. The sensing unit 110 may furtherinclude an analog to digital converter (ADC) (not shown) which convertsthe integrated data by the receiver into digital data. Later, thedigital data may be input to a processor (not shown) and processed toobtain information on the touch on the touch sensor panel 100. Thesensing unit 110 may include the ADC and processor as well as thereceiver.

A controller 130 may perform a function of controlling the operations ofthe drive unit 120 and the sensing unit 110. For example, the controller130 generates and transmits a drive control signal to the drive unit120, so that the drive signal can be applied to a predetermined driveelectrode TX1 for a predetermined time period. Also, the controller 130generates and transmits the drive control signal to the sensing unit110, so that the sensing unit 110 may receive the sensing signal fromthe predetermined receiving electrode RX for a predetermined time periodand perform a predetermined function.

In FIG. 1a , the drive unit 120 and the sensing unit 110 may constitutea touch detection device (not shown) capable of detecting whether thetouch has occurred on the touch sensor panel 100 according to theembodiment of the present invention or not and where the touch hasoccurred. The touch detection device according to the embodiment of thepresent invention may further include the controller 130. The touchdetection device according to the embodiment of the present inventionmay be integrated and implemented on a touch sensing integrated circuitIC in a touch input device 1000 including the touch sensor panel 100.The drive electrode TX and the receiving electrode RX included in thetouch sensor panel 100 may be connected to the drive unit 120 and thesensing unit 110 included in touch sensing IC (not shown) through, forexample, a conductive trace and/or a conductive pattern printed on acircuit board, or the like. The touch sensing IC may be placed on acircuit board on which the conductive pattern has been printed, forexample, a first printed circuit board (hereafter, referred to as afirst PCB). According to the embodiment, the touch sensing IC (notshown) may be mounted on a main board for operation of the touch inputdevice 1000.

As described above, a capacitance (C) with a predetermined value isformed at each crossing of the drive electrode TX and the receivingelectrode RX. When an object U such as a finger, palm, stylus, etc.,approaches close to the touch sensor panel 100, the value of thecapacitance may be changed. In FIG. 1a , the capacitance may represent amutual capacitance (Cm). The sensing unit 110 senses such electricalcharacteristics, thereby detecting whether the touch has occurred on thetouch sensor panel 100 or not and where the touch has occurred. Forexample, the sensing unit 110 is able to detect whether the touch hasoccurred on the surface of the touch sensor panel 100 comprised of atwo-dimensional plane consisting of a first axis and a second axis.

More specifically, when the touch occurs on the touch sensor panel 100,the drive electrode TX to which the drive signal has been applied isdetected, so that the position of the second axial direction of thetouch can be detected. Likewise, when the touch occurs on the touchsensor panel 100, the capacitance change is detected from the receptionsignal received through the receiving electrode RX, so that the positionof the first axial direction of the touch can be detected.

The touch sensor panel 100 for detecting where the touch has occurred inthe touch input device 1000 according to the embodiment of the presentinvention may be positioned outside or inside a display module 200.

The display module of the touch input device 1000 according to theembodiment of the present invention may be a display panel included in aliquid crystal display (LCD), a plasma display panel (PDP), an organiclight emitting diode (OLED), etc. Accordingly, a user may perform theinput operation by touching the touch surface while visually identifyingan image displayed on the display panel. Here, the display module 200may include a control circuit which receives an input from anapplication processor (AP) or a central processing unit (CPU) on a mainboard for the operation of the touch input device 1000 and displays thecontents that the user wants on the display panel. The control circuitmay be mounted on a second printed circuit board (hereafter, referred toas a second PCB). Here, the control circuit for the operation of thedisplay module 200 may include a display panel control IC, a graphiccontroller IC, and a circuit required to operate other display modules200.

While the foregoing has described the operation of the touch sensorpanel 100 detecting the touch position on the basis of a mutualcapacitance change amount between the drive electrode TX and thereceiving electrode RX, the present invention is not limited to this.That is, as shown in FIG. 2, it is possible to detect the touch positionon the basis of a self-capacitance change amount.

FIG. 2 is a schematic view for describing a capacitance type touchsensor panel 100 and the operation thereof in accordance with anotherembodiment of the present invention. A plurality of touch electrodes 30are provided on the touch sensor panel 100 shown in FIG. 2. Although theplurality of touch electrodes 30 may be, as shown in FIG. 2, disposed ata regular interval in the form of a grid, the present invention is notlimited to this.

The drive control signal generated by the controller 130 is transmittedto the drive unit 120. On the basis of the drive control signal, thedrive unit 120 applies the drive signal to the predetermined touchelectrode 30 for a predetermined time period. Also, the drive controlsignal generated by the controller 130 is transmitted to the sensingunit 110. On the basis of the drive control signal, the sensing unit 110receives the sensing signal from the predetermined touch electrode 30for a predetermined time period. Here, the sensing signal may be asignal for the change amount of the self-capacitance formed on the touchelectrode 30.

Here, whether the touch has occurred on the touch sensor panel 100 ornot and/or the touch position are detected by the sensing signaldetected by the sensing unit 110. For example, since the coordinate ofthe touch electrode 30 has been known in advance, whether the touch ofthe object U on the surface of the touch sensor panel 100 has occurredor not and/or the touch position can be detected.

The foregoing has described in detail the touch sensor panel 100detecting the touch position on the basis of the mutual capacitancechange amount and the self-capacitance change amount. However, in thetouch input device 1000 according to the embodiment of the presentinvention, the touch sensor panel 100 for detecting whether or not thetouch has occurred and the touch position may be implemented by usingnot only the above-described method but also any touch sensing methodsuch as a surface capacitance type method, a projected capacitance typemethod, a resistance film method, a surface acoustic wave (SAW) method,an infrared method, an optical imaging method, a dispersive signaltechnology, and an acoustic pulse recognition method, etc.

FIGS. 3a to 3e are conceptual views showing a relative position of thetouch sensor panel with respect to the display module in the touch inputdevice according to the embodiment of the present invention.

First, a relative position of the touch sensor panel 100 with respect tothe display module 200 using an LCD panel will be described withreference to FIGS. 3a to 3 c.

In this specification, a reference numeral 200 designates the displaymodule. However, the reference numeral 200 in FIGS. 3a to 3e and thedescriptions thereof may designate a display panel as well as thedisplay module.

As shown in FIGS. 3a to 3c , the LCD panel may include a liquid crystallayer 250 including a liquid crystal cell, a first glass layer 261 and asecond glass layer 262 which are disposed on both sides of the liquidcrystal layer 250 and include electrodes, a first polarizer layer 271formed on a side of the first glass layer 261 in a direction facing theliquid crystal layer 250, and a second polarizer layer 272 formed on aside of the second glass layer 262 in the direction facing the liquidcrystal layer 250. Here, the first glass layer 261 may be color filterglass, and the second glass layer 262 may be TFT glass.

It is clear to those skilled in the art that the LCD panel may furtherinclude other configurations for the purpose of performing thedisplaying function and may be transformed.

FIG. 3a shows that the touch sensor panel 100 of the touch input device1000 is disposed outside the display module 200. The touch surface ofthe touch input device 1000 may be the surface of the touch sensor panel100. In FIG. 3a , the top surface of the touch sensor panel 100 is ableto function as the touch surface. Also, according to the embodiment, thetouch surface of the touch input device 1000 may be the outer surface ofthe display module 200. In FIG. 3a , the bottom surface of the secondpolarizer layer 272 of the display module 200 is able to function as thetouch surface. Here, in order to protect the display module 200, thebottom surface of the display module 200 may be covered with a coverlayer (not shown) like glass.

FIGS. 3b and 3c show that the touch sensor panel 100 of the touch inputdevice 1000 is disposed inside the display module 200. Here, in FIG. 3b, the touch sensor panel 100 for detecting the touch position isdisposed between the first glass layer 261 and the first polarizer layer271. Here, the touch surface of the touch input device 1000 is the outersurface of the display module 200. The top surface or bottom surface ofthe display module 200 in FIG. 3b may be the touch surface. FIG. 3cshows that the touch sensor panel 100 for detecting the touch positionis included in the liquid crystal layer 250. Here, the touch surface ofthe touch input device 1000 is the outer surface of the display module200. The top surface or bottom surface of the display module 200 in FIG.3c may be the touch surface. In FIGS. 3b and 3c , the top surface orbottom surface of the display module 200, which can be the touchsurface, may be covered with a cover layer (not shown) like glass.

The foregoing has described whether the touch has occurred on the touchsensor panel 100 according to the embodiment of the present or not andwhere the touch has occurred. Further, through use of the touch sensorpanel 100 according to the embodiment of the present, it is possible todetect the magnitude of the touch pressure as well as whether the touchhas occurred or not and where the touch has occurred. Also, apart fromthe touch sensor panel 100, it is possible to detect the magnitude ofthe touch pressure by further including the pressure detection modulewhich detects the touch pressure.

Next, a relative position of the touch sensor panel 100 with respect tothe display module 200 using an OLED panel will be described withreference to FIGS. 3d and 3e . In FIG. 3d , the touch sensor panel 100is positioned between a polarizer layer 282 and a first glass layer 281.In FIG. 3e , the touch sensor panel 100 is positioned between an organicmaterial layer 280 and a second glass layer 283.

Here, the first glass layer 281 may be made of encapsulation glass. Thesecond glass layer 283 may be made of TFT glass. Since the touch sensinghas been described above, the other configurations only will be brieflydescribed.

The OLED panel is a self-light emitting display panel which uses aprinciple where, when current flows through a fluorescent orphosphorescent organic thin film and then electrons and electron holesare combined in the organic material layer, so that light is generated.The organic matter constituting the light emitting layer determines thecolor of the light.

Specifically, the OLED uses a principle in which when electricity flowsand an organic matter is applied on glass or plastic, the organic matteremits light. That is, the principle is that electron holes and electronsare injected into the anode and cathode of the organic matterrespectively and are recombined in the light emitting layer, so that ahigh energy exciton is generated and the exciton releases the energywhile falling down to a low energy state and then light with aparticular wavelength is generated. Here, the color of the light ischanged according to the organic matter of the light emitting layer.

The OLED includes a line-driven passive-matrix organic light-emittingdiode (PM-OLED) and an individual driven active-matrix organiclight-emitting diode (AM-OLED) in accordance with the operatingcharacteristics of a pixel constituting a pixel matrix. None of themrequire a backlight. Therefore, the OLED enables a very thin displaymodule to be implemented, has a constant contrast ratio according to anangle and obtains a good color reproductivity depending on atemperature. Also, it is very economical in that non-driven pixel doesnot consume power.

In terms of operation, the PM-OLED emits light only during a scanningtime at a high current, and the AM-OLED maintains a light emitting stateonly during a frame time at a low current. Therefore, the AM-OLED has aresolution higher than that of the PM-OLED and is advantageous fordriving a large area display panel and consumes low power. Also, a thinfilm transistor (TFT) is embedded in the AM-OLED, and thus, eachcomponent can be individually controlled, so that it is easy toimplement a delicate screen.

As shown in FIGS. 3d and 3e , basically, the OLED (particularly,AM-OLED) panel includes the polarizer layer 282, the first glass layer281, the organic layer 280, and the second glass layer 283. Here, thefirst glass layer 281 may be made of encapsulation glass. The secondglass layer 283 may be made of TFT glass. However, they are not limitedto this.

Also, the organic layer 280 may include a hole injection layer (HIL), ahole transport layer (HTL), an electron injection layer (EIL), anelectron transport layer (ETL), and a light-emitting layer (EML).

Briefly describing each of the layers, HIL injects electron holes and ismade of a material such as CuPc, etc. HTL functions to move the injectedelectron holes and mainly is made of a material having a good holemobility. Arylamine, TPD, and the like may be used as the HTL. The EILand ETL inject and transport electrons. The injected electrons andelectron holes are combined in the EML and emit light. The EMLrepresents the color of the emitted light and is composed of a hostdetermining the lifespan of the organic matter and an impurity (dopant)determining the color sense and efficiency. This just describes thebasic structure of the organic layer 280 include in the OLED panel. Thepresent invention is not limited to the layer structure or material,etc., of the organic layer 280.

The organic layer 280 is inserted between an anode (not shown) and acathode (not shown). When the TFT becomes an on-state, a driving currentis applied to the anode and the electron holes are injected, and theelectrons are injected to the cathode. Then, the electron holes andelectrons move to the organic layer 280 and emit the light.

Up to now, the touch position detection by the touch sensor panel 100according to the embodiment of the present invention has been described.Additionally, through use of the touch sensor panel 100 according to theembodiment of the present invention, it is possible to detect themagnitude of the touch pressure as well as whether the touch hasoccurred or not and/or the touch position. Also, apart from the touchsensor panel 100, it is possible to detect the magnitude of the touchpressure by further including the pressure detection module whichdetects the touch pressure. Hereafter, the touch pressure detectionusing the pressure detection module will be described in detail.

In the touch sensor panel 100 according to the embodiment of the presentinvention, the touch position can be detected through theabove-described touch sensor panel 100, and the touch pressure can bedetected by disposing the pressure detection module 400 between thedisplay module 200 and a substrate 300.

Hereinafter, the touch pressure detection by the pressure detectionmodule 400 of the touch input device 1000 according to the embodiment ofthe present invention, and the structure thereof will be described.

FIGS. 4a and 4b show a method and structure for performing the touchpressure detection by detecting the mutual capacitance change amount.The pressure detection module 400 shown in FIGS. 4a and 4b includes aspacer layer 420 composed of, for example, an air-gap. In anotherembodiment, the spacer layer 420 may be composed of an impact absorbingmaterial or may be filled with a dielectric material.

The pressure detection module 400 may include a pressure electrode 450and 460 located within the spacer layer 420. Here, the pressureelectrode 450 and 460 may be formed under the display module 200 invarious ways. This will be described below in more detail. Since thepressure electrode 450 and 460 is included in the rear side of thedisplay panel, the pressure electrode 450 and 460 can be made of any oneof a transparent material or an opaque material.

In order to maintain the spacer layer 420, an adhesive tape 440 with apredetermined thickness may be formed along the circumference of theupper portion of the substrate 300. The adhesive tape 440 may be formedon the entire circumference of the substrate 300 (e.g., four sides of aquadrangle) or may be formed on some of the circumference. For example,the adhesive tape 440 may be attached to the top surface or to thebottom surface of the display module 200. The adhesive tape 440 may be aconductive tape in order that the substrate 300 and the display module200 have the same electric potential. Also, the adhesive tape 440 may bea double adhesive tape. In the embodiment of the present invention, theadhesive tape 440 may be made of an inelastic material. In theembodiment of the present invention, when a pressure is applied to thedisplay module 200, the display module 200 may be bent. Therefore, themagnitude of the touch pressure can be detected even though the adhesivetape 440 is not transformed by the pressure.

As shown in FIGS. 4a and 4b , the pressure electrode for detecting thepressure includes the first electrode 450 and the second electrode 460.Here, any one of the first electrode 450 and the second electrode 460may be a drive electrode, and the other may be a receiving electrode. Adrive signal is applied to the drive electrode, and a sensing signal maybe obtained through the receiving electrode. When voltage is applied,the mutual capacitance may be generated between the first electrode 450and the second electrode 460.

FIG. 4b is a cross sectional view of the pressure detection module 400when a pressure is applied by the object U. The bottom surface of thedisplay module 200 may have a ground potential in order to block thenoise. When the pressure is applied to the surface of the touch sensorpanel 100 by the object U, the touch sensor panel 100 and the displaymodule 200 may be bent.

As a result, a distance “d” between the pressure electrode pattern 450and 460 and a reference potential layer having the ground potential maybe reduced to “d′”. In this case, due to the reduction of the distance“d”, fringing capacitance is absorbed in the bottom surface of thedisplay module 200, so that the mutual capacitance between the firstelectrode 450 and the second electrode 460 may be reduced. Therefore,the magnitude of the touch pressure can be calculated by obtaining thereduction amount of the mutual capacitance from the sensing signalobtained through the receiving electrode.

In the touch input device 1000 according to the embodiment of thepresent invention, the display module 200 may be bent by the appliedpressure of the touch. The display module 200 may be bent in such amanner as to show the biggest transformation at the touch position. Whenthe display module 200 is bent according to the embodiment, a positionshowing the biggest transformation may not match the touch position.However, the display module 200 may be shown to be bent at least at thetouch position. For example, when the touch position approaches close tothe border, edge, etc., of the display module 200, the most bentposition of the display module 200 may not match the touch position.However, the display module 200 may be shown to be bent at least at thetouch position.

Here, the top surface of the substrate 300 may also have the groundpotential in order to block the noise. Therefore, in order to preventthe substrate 300 and the pressure electrode 450 and 460 from beingshort-circuited, the pressure electrode 450 and 460 may be formed on aninsulation layer.

FIGS. 5, 6 a, and 6 b show a method for detecting the touch pressure bydetecting the self-capacitance change amount, and a structure of thesame.

The pressure detection module 400 for detecting the self-capacitancechange amount uses a pressure electrode 455 formed on the bottom surfaceof the display module 200. When a drive signal is applied to thepressure electrode 455, the pressure electrode 455 receives a signalincluding information on the self-capacitance change amount and thendetects the touch pressure.

The drive unit 120 applies a drive signal to the pressure electrode 455,and the sensing unit 110 measures a capacitance between the pressureelectrode 455 and the reference potential layer 300 (e.g., substrate)having a reference potential through the pressure electrode 455, therebydetecting whether the touch pressure has been applied or not and themagnitude of the touch pressure.

The drive unit 120 may include, for example, a clock generator (notshown) and a buffer, generate a pulse-shaped drive signal, and apply thedrive signal to the pressure electrode 455. However, this is just anexample. The drive unit may be implemented by means of various elements,and the shape of the drive signal may be variously changed.

The drive unit 120 and the sensing unit 110 may be implemented by anintegrated circuit and may be formed on one chip. The drive unit 120 andthe sensing unit 110 may constitute a pressure detector.

In order that the capacitance change amount is easily detected betweenthe pressure electrode 455 and the reference potential layer 300, thepressure electrode 455 may be formed such that a larger facing surfacebetween the pressure electrode 455 and the reference potential layer300. For example, the pressure electrode 455 may be formed in aplate-like pattern.

With regard to the detection of the touch pressure in theself-capacitance type method, here, one pressure electrode 455 is takenas an example for description. However, the plurality of electrodes areincluded and a plurality of channels are constituted, so that it ispossible to configure that the magnitude of multi pressure can bedetected according to multi touch.

The capacitance between the pressure electrode 455 and the referencepotential layer is changed by the change of the distance between thepressure electrode 455 and the reference potential layer 300. Then, thesensing unit 110 detects information on the capacitance change, and thusthe touch pressure is detected.

FIG. 6a is a cross sectional view showing the display module 200 and thepressure detection module 400 in the touch input device 1000.

As with the above-described embodiment of FIGS. 4a and 4b , the pressureelectrode 455 may be disposed apart from the reference potential layer300 at a predetermined distance “d”. Here, a material which isdeformable by the pressure applied by the object U may be disposedbetween the pressure electrode 455 and the reference potential layer300. For instance, the deformable material disposed between the pressureelectrode 455 and the reference potential layer 300 may be air,dielectrics, an elastic body and/or a shock absorbing material.

When the object U presses the touch surface (herein, the top surface ofthe display module 200 or the top surface of the touch sensor panel100), the pressure electrode 455 and the reference potential layer 300become close to each other by the applied pressure, and the spaceddistance “d” between them becomes smaller.

FIG. 6b shows that the pressure is applied by the object U and then thedisplay module 200 and the pressure detection module 400 are bentdownwardly. As the distance between the pressure electrode 455 and thereference potential layer 300 is reduced from “d” to “d′”, thecapacitance is changed. Specifically, the self-capacitance generatedbetween the pressure electrode 455 and the reference potential layer 300is increased. The thus generated self-capacitance change amount is, asdescribed above, measured by the sensing unit 110. Through this, it ispossible to determine whether or not the touch pressure has been appliedand the magnitude of the touch pressure.

As described above, the touch input device 1000 according to theembodiment of the present invention includes the electrode of the touchsensor panel 100, which is for detecting the touch position, and theelectrode of the pressure detection module 400 which is for detectingthe touch pressure. Specifically, with regard to the touch positiondetection, there exist the drive electrode and the receiving electrodewhich detect the mutual capacitance change amount, and the touchelectrode (which may be any one of the drive electrode and the receivingelectrode) which detects the self-capacitance change amount.

Also, with regard to the touch pressure detection, there exist the driveelectrode and the receiving electrode which detect the mutualcapacitance change amount, and the pressure electrode (which may be anyone of the drive electrode and the receiving electrode) which detectsthe self-capacitance change amount. Hereinafter, various arrangementsand structures of the electrodes included in the touch input device 1000according to the embodiment of the present invention will be described.

FIG. 7 is a cross sectional vies showing the arrangement of each of theelectrodes in the touch input device 1000 according to the embodiment ofthe present invention. Specifically, in the embodiment of FIG. 7,electrodes 10 and 20 detecting the touch position and an electrode RX_pdetecting the touch pressure are provided to the inside of the displaymodule 200 including the LCD panel.

The display module 200 includes the liquid crystal layer 250 between thefirst glass layer 261 and the second glass layer 262. A spacer S forobtaining a predetermined interval may be provided in the liquid crystallayer 250 of the display module 200. The spacer S can be used as areference electrode GND by forming a conductive material, e.g., ITO onthe spacer S.

The reference electrode GND formed on the spacer S may be spaced apartfrom the pressure electrode RX_p for detecting the touch pressure by apredetermined interval. Specifically, the pressure electrode RX_p may bethe electrode 455 indicated by a reference numeral 455 in FIG. 5. Inother words, the pressure electrode RX_p detects the self-capacitancechange amount between the reference electrode GND and the pressureelectrode RX_p.

Describing in more detail, the drive unit 120 applies a drive signal tothe pressure electrode RX_p. The sensing unit 110 measures a capacitancebetween the pressure electrode RX_p and the reference electrode GNDthrough the pressure electrode RX_p, thereby detecting whether the touchpressure has been applied or not and the magnitude of the touchpressure.

The drive unit 120 may include, for example, a clock generator (notshown) and a buffer, generate a pulse-shaped drive signal, and thenapply the drive signal to the pressure electrode RX_p. However, this isjust an example. The drive unit may be implemented by means of variouselements and the shape of the drive signal can be variously changed.

The drive unit 120 and the sensing unit 110 may be implemented by anintegrated circuit and may be formed on one chip. The drive unit 120 andthe sensing unit 110 may constitute a pressure detector.

In order that the capacitance change amount is easily detected betweenthe pressure electrode RX_p and the reference electrode GND formed onthe spacer S, the pressure electrode RX_p may be formed such that alarger facing surface between the pressure electrode RX_p and thereference electrode GND. For example, the pressure electrode RX_p may beformed in a plate-like pattern.

With regard to the detection of the touch pressure in theself-capacitance type method, here, one pressure electrode RX_p is takenas an example for description. However, the plurality of electrodes areincluded and a plurality of channels are constituted, so that it ispossible to configure that the magnitude of multi pressure can bedetected according to multi touch.

The capacitance between the pressure electrode RX_p and the referenceelectrode GND is changed by the change of the distance between thepressure electrode RX_p and the reference electrode GND. Then, thesensing unit 110 detects information on the capacitance change, and thusthe touch pressure is detected.

For this, the pressure electrode RX_p may be, as shown in FIG. 7,disposed within the liquid crystal layer 250 in such a manner as to bespaced apart from the reference electrode GND by a predetermineddistance.

When the object U presses the touch surface (herein, the top surface ofthe display module 200 or the top surface of the touch sensor panel100), the pressure electrode RX_p and the reference electrode GND becomeclose to each other by the applied pressure, and the spaced distancebetween them becomes smaller.

Accordingly, the self-capacitance generated between the pressureelectrode RX_p and the reference electrode GND is increased. The thusgenerated self-capacitance change amount is, as described above,measured by the sensing unit 110. Through this, it is possible todetermine whether or not the touch pressure has been applied and themagnitude of the touch pressure.

Meanwhile, the drive electrode 10 for detecting the touch position maybe formed on the second glass layer 262 within the liquid crystal layer250. The receiving electrode 20 may be formed on the first glass layer261. That is, the drive electrode 10 and the receiving electrode 20 areformed in different layers, and the touch position can be detected onthe basis of the change amount of the mutual capacitance formed betweenthe drive electrode 10 and the receiving electrode 20. Since this hasbeen described above in detail with reference to FIG. 1a , etc., thedescription thereof will be omitted.

Here, the second glass layer 262 may be comprised of various layersincluding a data line a gate line, TFT, a common electrode, and a pixelelectrode, etc. These electrical components may operate in such a manneras to generate a controlled electric field and orient liquid crystalslocated in the liquid crystal layer 250. The drive electrode 10 and thepressure electrode RX_p may use a common electrode included in thesecond glass layer 262.

FIG. 8a is a view schematically showing that each electrode has beenarranged according to the embodiment of FIG. 7.

As shown in FIG. 8a , for the purpose of detecting the touch position,provided are the drive electrode 10 of the liquid crystal layer 250,which is formed on the second glass layer 262, and the receivingelectrode 20 formed on the first glass layer 261.

The pressure electrode RX_p for detecting the touch pressure may beformed in the same layer in which the drive electrode 10 is formed, thatis, may be formed on the second glass layer 262 within the liquidcrystal layer 250. Here, as viewed from the top, the pressure electrodeRX_p may be, as shown in FIG. 8a , placed between the plurality of driveelectrodes 10. In other words, the pressure electrode RX_p and the driveelectrode 10 may be alternately formed in the same layer.

FIG. 8b is a cross sectional view showing that the drive electrode 10and the receiving electrode 20 are formed in the same layer within thedisplay module 200 in the touch input device according to the embodimentof the present invention. Since the touch position detection in such astructure has been described with reference to FIG. 1c , the descriptionthereof will be omitted.

In the electrode structure of FIG. 8b , the pressure electrode RX_p maybe also formed in the same layer (for example, the second glass layer262) in which the drive electrode 10 and the receiving electrode 20 havebeen formed.

A capacitance (C) with a predetermined value is formed at each crossingof the drive electrode TX and the receiving electrode RX. When theobject U such as a finger, palm, stylus, etc., approaches, the value ofthe capacitance may be changed. The touch position can be detected basedon the capacitance change amount.

FIG. 9 is a cross sectional view showing the arrangement of each of theelectrodes in the touch input device according to another embodiment ofthe present invention. Also, in the embodiment of FIG. 9, the referenceelectrode GND may be formed on the spacer S. The self-capacitance changeamount according to the change of a distance between the referenceelectrode GND and the pressure electrode RX_p formed separately from thereference electrode GND is detected, so that the touch pressure isdetected.

The touch electrode 30 detecting the touch position may be formed on thesecond glass layer 262 within the liquid crystal layer 250. The drivecontrol signal generated by the controller 130 is transmitted to thedrive unit 120. On the basis of the drive control signal, the drive unit120 applies the drive signal to the predetermined touch electrode 30 fora predetermined time period. Also, the drive control signal generated bythe controller 130 is transmitted to the sensing unit 110. On the basisof the drive control signal, the sensing unit 110 receives the sensingsignal from the predetermined touch electrode 30 for a predeterminedtime period. Here, whether the touch has occurred on the touch sensorpanel 100 or not and/or the touch position are detected by the sensingsignal detected by the sensing unit 110. For example, since thecoordinate of the touch electrode 30 has been known in advance, whetherthe touch of the object U on the surface of the touch sensor panel 100has occurred or not and/or the touch position can be detected.

FIGS. 10a and 10b are views schematically showing that each electrodehas been arranged according to the embodiment of FIG. 9. That is, thequadrangular touch electrode 30 for detecting the touch position byusing the self-capacitance change amount is arranged at a predeterminedinterval in the form of a grid. However, this is just an example. Theshape and arrangement of the touch electrode 30 may be changed.

Here, as with the touch electrode 30, the pressure electrode RX_p may beformed on the second glass layer 262 within the liquid crystal layer250. The pressure electrode RX_p may be properly disposed in a spacedspace between the plurality of touch electrodes 30.

That is, as shown in FIG. 10a , the pressure electrode RX_p may beformed in the spaced space of the plurality of touch electrodes 30 inthe form of a cross. Also, as shown in FIG. 10b , the pressure electrodeRX_p may be formed only in a vertical line or a horizontal line of thespaced space.

In the meantime, in another embodiment, as with the pressure electrodeRX_p, the plurality of touch electrodes 30 shown in FIG. 10a can be usedin sensing the pressure. In other words, the touch electrode 30 is ableto function as an electrode for sensing not only the touch position butalso the touch pressure. As such, when the touch electrode 30 is used asthe electrode for sensing the pressure, a larger number of the pressuresensing electrodes are formed, so that reliability is improved andsensitivity is increased. Also, the number of the pressure electrodesRX_p can be reduced, thereby helping to reduce the cost. In this case,the reference electrode is disposed under the plurality of touchelectrodes 30, and then the touch pressure can be detected on the basisof the self-capacitance change amount according to the change of adistance between the touch electrode 30 and the reference electrode.

In the descriptions of FIGS. 7 and 9, with regard to the arrangement ofthe pressure electrode RX_p and the reference electrode GND, it has beendescribed that the pressure electrode RX_p is formed on the second glasslayer 262, and the reference electrode GND formed on the spacer S isformed on the first glass layer 261. However, in another embodiment, anarrangement opposite to that above described may be made.

That is, if the reference electrode GND is formed on the spacer S formedon the second glass layer 262 within the liquid crystal layer 250, thepressure electrode RX_p may be formed on the first glass layer 261within the liquid crystal layer 250.

Also, in FIG. 7, it can be considered that the positions of the driveelectrode 10 and the receiving electrode 20 may be interchanged.

FIG. 11 is a cross sectional view showing that a pressure electrode hasbeen formed within the display module 200 including an OLED panel in thetouch input device according to the embodiment of the present invention.As shown in FIG. 11, the OLED includes the organic material layer 280between the first glass layer 281 and the second glass layer 283. Here,the pressure electrode RX_p for detecting the touch pressure by theself-capacitance type method may be formed on the second glass layer283. A light shield (LS) for shielding the light inflow, a gateelectrode, a source electrode, a drain electrode, a pixel electrode,etc., can be used as the pressure electrode RX_p. In some cases, thepressure electrode RX_p can be used to detect the pressure by depositingseparate metal material. Furthermore, a separate metallic configurationis provided and used to detect the pressure.

In the meantime, although FIG. 11 does not show the drive electrode andthe receiving electrode for detecting the touch position, they may bedisposed in the form shown FIGS. 3d and 3e . However, there is no limitto this. A skilled person in the art may be able to change thearrangement of the drive electrode and receiving electrode by variousmethods according to needs.

According to the above-described structure, the touch position detectionby the drive electrode and the receiving electrode and the touchpressure detection by the pressure electrode can be separately made, sothat the touch position and the touch pressure can be detected at thesame time.

The features, structures and effects and the like described in theembodiments are included in one embodiment of the present invention andare not necessarily limited to one embodiment. Furthermore, thefeatures, structures, effects and the like provided in each embodimentcan be combined or modified in other embodiments by those skilled in theart to which the embodiments belong. Therefore, contents related to thecombination and modification should be construed to be included in thescope of the present invention.

Although embodiments of the present invention were described above,these are just examples and do not limit the present invention. Further,the present invention may be changed and modified in various ways,without departing from the essential features of the present invention,by those skilled in the art. For example, the components described indetail in the embodiments of the present invention may be modified.Further, differences due to the modification and application should beconstrued as being included in the scope and spirit of the presentinvention, which is described in the accompanying claims.

What is claimed is:
 1. A touch input device detecting a touch positionand a touch pressure, the touch input device comprising: a displaymodule which comprises a first layer made of glass or plastic and asecond layer which is disposed under the first layer and is made ofglass or plastic; a plurality of touch electrodes which are formedwithin the display module and are for detecting the touch position andthe touch pressure; and a reference electrode which is disposed apartfrom the touch electrode; wherein a drive signal is applied to the touchelectrode and the touch position is detected by a sensing signalreceived from the touch electrode; wherein an electrical signal which ischanged by a capacitance between the touch electrode and the referenceelectrode is detected from the touch electrode; wherein the capacitanceis changed by a change of a distance between the touch electrode and thereference electrode; wherein the distance between the touch electrodeand the reference electrode is changed by a bend of the display module;and wherein the touch pressure is detected based on the capacitance. 2.The touch input device of claim 1, further comprising: a substrate whichis disposed under the display module; and a spacer layer which isdisposed between the touch electrode and the reference electrode;wherein a spacer layer retaining member having a predetermined thicknessis formed along the circumference of the upper portion of the substratein order to retain the spacer layer; wherein, when the display module isbent by applying a pressure to the display module, the spacer layerretaining member is not transformed; and wherein the reference electrodeis the substrate.
 3. The touch input device of claim 2, wherein thetouch electrode is formed on the top surface of the first layer.
 4. Thetouch input device of claim 3, wherein a liquid crystal layer isdisposed between the first layer and the second layer.
 5. The touchinput device of claim 3, wherein an organic material layer is disposedbetween the first layer and the second layer.
 6. The touch input deviceof claim 2, wherein the touch electrode is formed on the bottom surfaceof the first layer or on the top surface of the second layer.
 7. Thetouch input device of claim 6, wherein the touch electrode is a commonelectrode included in the display module.
 8. The touch input device ofclaim 6, wherein a liquid crystal layer is disposed between the firstlayer and the second layer.
 9. The touch input device of claim 6,wherein an organic material layer is disposed between the first layerand the second layer.
 10. A touch input device detecting a touchposition and a touch pressure, the touch input device comprising: adisplay module which comprises a first layer made of glass or plasticand a second layer which is disposed under the first layer and is madeof glass or plastic; a first electrode for detecting the touch positionand the touch pressure and a second electrode for detecting the touchposition, which are formed within the display module; and a referenceelectrode which is disposed apart from the first electrode; wherein adrive signal is applied to any one of the first electrode and the secondelectrode, and the touch position is detected by a sensing signalreceived from the other of the first electrode and the second electrode;wherein an electrical signal which is changed by a capacitance betweenthe first electrode and the reference electrode is detected from thefirst electrode; wherein the capacitance is changed by a change of adistance between the first electrode and the reference electrode;wherein the distance between the first electrode and the referenceelectrode is changed by a bend of the display module; and wherein thetouch pressure is detected based on the capacitance.
 11. The touch inputdevice of claim 10, further comprising: a substrate which is disposedunder the display module; and a spacer layer which is disposed betweenthe first electrode and the reference electrode; wherein a spacer layerretaining member having a predetermined thickness is formed along thecircumference of the upper portion of the substrate in order to retainthe spacer layer; wherein, when the display module is bent by applying apressure to the display module, the spacer layer retaining member is nottransformed; and wherein the reference electrode is the substrate. 12.The touch input device of claim 11, wherein the first electrode and thesecond electrode are formed on the top surface of the first layer. 13.The touch input device of claim 12, wherein a liquid crystal layer isdisposed between the first layer and the second layer.
 14. The touchinput device of claim 12, wherein an organic material layer is disposedbetween the first layer and the second layer.
 15. The touch input deviceof claim 11, wherein the first electrode and the second electrode areformed on the bottom surface of the first layer or on the top surface ofthe second layer.
 16. The touch input device of claim 15, wherein thefirst electrode or the second electrode is a common electrode includedin the display module.
 17. The touch input device of claim 15, wherein aliquid crystal layer is disposed between the first layer and the secondlayer.
 18. The touch input device of claim 15, wherein an organicmaterial layer is disposed between the first layer and the second layer.19. The touch input device of claim 11, wherein the second electrode isformed on the top surface of the first layer, and the first electrode isformed on the bottom surface of the first layer or on the top surface ofthe second layer.
 20. The touch input device of claim 19, wherein thefirst electrode is a common electrode included in the display module.21. The touch input device of claim 19, wherein a liquid crystal layeris disposed between the first layer and the second layer.
 22. The touchinput device of claim 19, wherein an organic material layer is disposedbetween the first layer and the second layer.